A viscoelastic-based model for predicting the strength of asphalt concrete in direct tension

•A viscoelastic continuum damage-based method is suggested to predict the strength of asphalt concrete in monotonic tension testing.•Suggested method incorporate result from cyclic test to predict monotonic test data.•The suggested method was verified for wide range of RAP content mixtures.•It is proved that VECD is able to predict stress drop in monotonic loading.•TSRST test result are successfully predicted by the suggested formula. The modeling of asphalt concrete behavior under monotonic loading plays an important role in investigating the low temperature behavior of pavement material. Further, any proposed method should be able to consider the rate and temperature dependency of asphalt concrete. This paper presents a new method for simulating the behavior of asphalt concrete in uniaxial tension. Direct tension monotonic testing that incorporates a constant crosshead displacement rate and various temperatures was used in the experimental investigation to simulate thermal cracking of asphalt concrete. Viscoelastic continuum damage theory was applied to simulate the asphalt behavior in direct tension. This theory is able to model distributed damage within the material under both constant and dropping temperatures. A damage characteristic curve, which has been proven to represent the intrinsic property of the material, was used to simulate the damage evolution during testing. The proposed method features a single ordinary differential equation that is solved to provide the damage evolution. The results show that the predicted stress matches the measured data well for tests conducted at North Carolina State University and by other agencies. Implementing the proposed method in a finite element code provides a strong mechanistic model to predict asphalt fracture under thermal loading.